- Artist Statement
- Installation Assembly
- Exhibition Requirements
- Code/Technical Operation
Element 4 (Weather Station Alpha) is a sculpture that is reflective of current real-time weather data displayed via LCD screens on a plinth.
The data is physically represented through the speed of the mechanisms used to represent each weather element. The gray colour of the plinth and the choice to use glass tubes were made having a smoke stack in mind. The black, brass, and copper details were all carefully chosen to point to an industrious, dystopian environment juxtaposing the real time data. Element 4 was created to begin a discussion around environmental issues and how weather manifests as a tactile, physical object.
Five major cities’ air pollution, wind speed, precipitation, and temperature are abstractly represented via the sculpture and its mechanisms.
Air pollution is represented by a black accordion-like tube that pulsates up and down. The higher the amount of air pollution, the faster the tube will move. The movement of the tube is to represent the breathing of life and the struggles people face living and breathing the air in highly polluted areas.
The wind component is made of an organic flower shape that spins. The faster the wind speed, the faster the flower turns. The flower is comprised of pieces of spray-painted tin foil and black garbage bags melted together.
A substance called ferrofluid represents precipitation. Ferrofluid is fluid that contains nano sized iron particles and is highly magnetized. The fluid is in a petri dish while magnets below it move up and down on either side creating a spiked pattern with the fluid in the dish. As the precipitation increases, the arms with the magnet move faster.
Three graduated Edison bulbs of different shapes and sizes represent temperature. As the temperature increases, the speed at which the bulbs flicker increases. Therefore as the temperature increases the bulbs seem to pulse faster.
Our environment is crucial to the evolution of life and each element of the sculpture is created in a way that breathes its own life. The natural elements chosen to be represented are all critical to our current environmental issues. This piece is making a statement about how drastically our weather and environment has changed over the years because of our ecological footprint. The world is slowly becoming more industrialized and the effects of climate change are more apparent than ever.
- 4 glass tubes (one enclosed with holes at the top)( various sizes)
- 3 black plugs (various sizes, for each corresponding glass tube)
- 4 Grove LCD screens with cases
- 5 copper pipes (various sizes)
- 4 Arduinos
- 1 Raspberry Pi
- 1 Breadboard
- 3 servo motors
- 3 Edison bulbs (various sizes)
- 3 light bulb sockets
- 1 light circuit board
- 1 petridish
- 20 ml ferrofluid
- 2 magnets
- 1 mechanical arm
- 1 black accordion tube
- 1 metal/plastic flower shape
The piece is designed to be moved as a single unit. All power/control circuitry is fixed to the inside of the wooden plinth, and the moving sculptures on top are fixed to the inside. The only removable pieces are the glass tubes surrounding the element sculptures, which simply rest on the surface of the piece. These can be placed on top after the work is installed.
To begin operation, the piece simply needs to be plugged into the wall using the cord protruding from the bottom (5v). For internet access, the attached ethernet cable must be plugged to an open internet source. Currently the system is configured to connect to the University of Waterloo secured network, but should also work with any open ethernet connection. If a different authenticated network is required, the Raspberry Pi inside the piece will need to be reconfigured for the new network credentials.
Due to the fact that the piece emits sound as well as bright light, it would ideally be shown in a room of average brightness with no daylight and relative silence. The sounds emitted by the motors and light switching circuit are part of the overall effect, and must be easily audible by audiences. There should also be sufficient space on all sides of the piece for viewers to walk around and view from all angles. The sculpture is meant to be left running continuously so that data can be compared.
The circuitry that is used to control the three servo motors and three light bulbs is shown below. Here, the yellow block represents the 120VAC light relay circuit. This circuit can be found below the servo motor control circuit diagram. While no connections are shown between the LCD screens and the arduinos, in the final installation the LCD screens were connected to the arduinos via an I2C connection board provided by the class instructors.
There are actually three of the above light circuits being controlled by one arduino. Each digital pin (3 in total) controls one of the lights.
The circuit cabling has been glued and taped inside the structure in order to keep it from tangling around the motors. While no fuses were used in the circuitry, the circuit was deemed safe through testing. The components, especially the relay, have a factor of safety of two.
The wind mechanism is perhaps the simplist. Due to time restraints, a more detailed mounting system could not be machined in time for final installation. A 6202RS bearing holds the copper tube in place, while a DC motor shaft is epoxied in the center of the pipe, and to the bottom of the top plate. This mechanism is the most likely to fail, but it is also the simplest to fix.
The precipitation mechanism is a simple piston style linkage that converts the rotary motion of a DC motor with a cam attached, to the linear motion that actuates the magnets into and out of the field of the ferrofluid. The linkage is made of a brass rod with two washers epoxied at either end. The linkage slides through a small hole drilled in the top lid. The magnet linkages were handmade in the woodshop and they are the only pieces in existence. If these linkages break, new linkages will have to be made.
The air quality tube is held in place entirely by gravity. It rests on a linkage that is attached to a dc motor inside the structure. In order to get the fitting right, a piece of wood was attached to the shaft of the motor, with holes drilled at set increments from the shaft. This allowed for the length of linear movement to be adjusted on the fly with ease. This mechanism has a tendancy to push on the glass tube, but this actually adds to the feeling that it is alive, and trying to escape from a toxic environment.
The main brain of the piece is a Raspberry Pi 2 microprocessor running Raspbian Linux. It is configured to automatically start the code that runs the piece through a tool called Supervisord. This program ensures that the code is always running, and if it crashes for any reason it will be restarted. It also takes care of pulling the latest code from git, so that when the piece is turned on everything is up-to-date. As a result, our team can update the code remotely, adding more cities and changing timings and behaviour, all with a simple power cycle of the piece itself. This code is available at http://github.com/ajwootto/techart.
Connected to the Raspberry Pi are four Arduino Unos, each using a Grove accessory shield provided by the Arts department. The shields are responsible for connecting to the four LCD screens (one per Arduino). Unfortunately, due to the protocol the LCDs use, each Arduino could only drive one screen, necessitating the use of all four. Each Arduino is loaded with an identical program which changes its behaviour depending on the element assigned to it. This makes the code very maintainable because it removes the need for separate code bases for each element, and shares common functionality such as the LCD and serial communication. On bootup time, the Raspberry Pi sends a special command to each Arduino informing it of what element it must be. Luckily, the serial ports are assigned in the same order on each bootup as long as the Arduinos remain plugged in to the same USB ports, so once the correct order has been established in the code it doesn’t need to be changed.
The weather data itself is pulled from two different sources. Firstly, a free API called the OpenWeatherMap (http://openweathermap.org/) was used for the temperature, rain and wind data. It allows a generous number of free requests per hour, and provides the data in an easily digestible JSON format. The air pollution data was more complicated; no free API exists to retrieve this data, thus it had to be scraped from a website that provides it visually. This was accomplished using a Python library called lxml which parses HTML documents and can retrieve information using CSS selectors. The website the data was sourced from is (http://aqicn.org/) which aggregates many air pollution data sources into one world-wide map. Unfortunately, it does not include information for all cities, which limited our selection for the piece. The website URL is accessed for each city, and information is scraped and combined with the weather API data.